先在桌面上新建一个txt的文件名称为1,把下面的文字拷到里面，把扩展名改为reg:

　　Windows Registry Editor Version 5.00

　　[HKEY_CLASSES_ROOTpiffile]

　　@="Shortcut to MS-DOS Program"

　　"EditFlags"=hex:01,00,00,00

　　"IsShortcut"=""

　　"NeverShowExt"=""

　　"FriendlyTypeName"=hex(2)：40,00,25,00,53,00,79,00,73,00,74,00,65,00,6d,00,52,

　　00,6f,00,6f,00,74,00,25,00,5c,00,53,00,79,00,73,00,74,00,65,00,6d,00,33,00,

　　32,00,5c,00,61,00,63,00,70,00,70,00,61,00,67,00,65,00,2e,00,64,00,6c,00,6c,

　　00,2c,00,2d,00,36,00,30,00,30,00,35,00,00,00

　　[HKEY_CLASSES_ROOTpiffileshell]

　　[HKEY_CLASSES_ROOTpiffileshellopen]

　　[HKEY_CLASSES_ROOTpiffileshellopencommand]

　　@=""%1" %*"

　　[HKEY_CLASSES_ROOTpiffileshellex]

　　[HKEY_CLASSES_ROOTpiffileshellexContextMenuHandlers]

　　[HKEY_CLASSES_ROOTpiffileshellexContextMenuHandlersAVG8 Shell Extension]

　　@="{9F97547E-4609-42C5-AE0C-81C61FFAEBC3}"

　　[HKEY_CLASSES_ROOTpiffileshellexDropHandler]

　　@="{86C86720-42A0-1069-A2E8-08002B30309D}"

　　[HKEY_CLASSES_ROOTpiffileshellexIconHandler]

　　@="{00021401-0000-0000-C000-000000000046}"

　　[HKEY_CLASSES_ROOTpiffileshellexPropertySheetHandlers]

　　[HKEY_CLASSES_ROOTpiffileshellexPropertySheetHandlersPifProps]

　　@="{86F19A00-42A0-1069-A2E9-08002B30309D}"

　　[HKEY_CLASSES_ROOTpiffileshellex